The present invention relates to intermediates for phosphonomethoxy nucleotide analogs, in particular intermediates suitable for use in the efficient oral delivery of such analogs.
Such analogs per se and various technologies for oral delivery of these and other therapeutic compounds are known. See WO 91/19721, WO 94/03476, WO 94/03466, WO 92/13869, U.S. Pat. Nos. 5,208,221, 5,124,051, DE 41 38 584 A1, WO 94/10539, WEJ7368583647920, WO 95 79/07919, WO 92/09611, WO 92/01698, WO 91/19721, WO 88/05438, EP 0 632 048, EP 0 481 214, EP 0 369 409, EP 0 269 947, U.S. Pat. Nos. 3,524,846 and 5,386,030, Engel, Chem. Rev. 77:349-367 1977, Farquhar et al., J. Pharm. Sci. 72:324-325 1983, Starrett et al., Antiviral Res. 19:267-273 1992, Safadi et al., Pharmaceutical Research 10(9):1350-1355 1993, Sakamoto et al., Chem. Pharm. Bull. 32(6):2241-2248 1984, and Davidsen et al., J. Med. Chem. 37(26):4423-4429 1994.